The eVD4 series adds ABB's smart Relion protection and control technology and leading edge sensor technology to its well proven VD4 mechanically actuated circuit breakers. Since the VD4 was launched in 1987, over 550,000 units have been installed globally in a wide range of exacting applications where they have demonstrated excellent reliability and versatility. The eVD4 is delivered ready to install in the switchgear panel, this drastically reduces the need for wiring or additional work while its auxiliary circuit plug enables it to be instantly hooked up to the control circuit.

eVD4 circuit-breakers are available in fixed and withdrawable versions for UniGear ZS1 switchgear and PowerCube units. They cover the most common MV circuit breaker ratings, with a nominal voltage up to 17.5 kV, current up to 2,000 A and a breaking capacity up to 40 kA.
 
Integrated protection and monitoring relay and sensors
The eVD4 comes with ABB Relion^® technology built-in, in the form of the RBX615 protection and monitoring unit. This IED (Intelligent Electronic Device) is designed for protecting, monitoring, measuring and supervising applications in substations, as well as industrial and utility electrical installations and is suitable for any radial distribution network, regardless of the neutral earthing method used.

The combination of the RBX615 relay and the integrated current and voltage measuring sensors enable the eVD4 circuit-breaker to accurately and reliably monitor and record the network parameters, and to also provide protection functions.

The RBX615 unit conforms to IEC 61850 standards and uses GOOSE (Generic Object Oriented Substation Event) communication in the native mode. Switchgear units based on Relion technology are able to communicate with each other and, by means of a network switch, with the substation's control system.

Current and voltage sensors
eVD4 circuit breakers use current sensors or combined current-voltage sensors (Combisensors) to measure the current and voltage in each phase. These sensors do not include a ferromagnetic core, so thanks to the absence of hysteresis and saturation phenomena, they are able to provide accurate measurements, right up to the adjustable maximum value setting of the protection thresholds.

Just two sensor sizes are able to cover the entire current and voltage range, up to the maximum rated values of the circuit breaker.

Increased reliability
The integrated construction significantly reduces the mean time to repair (MTTR) for eVD4 circuit breakers compared with systems based on conventional components. If a fault occurs, the circuit breaker is simply replaced, enabling the unit to be immediately restored to full operation without impairing service continuity.

Simplified project specifications
The same circuit breaker can be used for a wide variety of applications by simply adjusting its parameters via software. This drastically reduces the number of spare parts and allows the circuit breaker to be specified at the beginning of the design process before the exact network requirements have been defined.

There is also no need to define the sensor parameters because they are established by the circuit breaker data and by the protection profile. The integrated protection and monitoring unit, complete with current and voltage sensors, simplifies the switchgear wiring operations reducing the risk of error. This speeds up the engineering and commissioning phases. Correct operation of the circuit breaker, components and protection functions is guaranteed because all the protection and control logic settings are tested in the factory.

Fast ordering and delivery
The eVD4’s integrated design also makes ordering and delivery faster and easier since all the switchgear equipment (circuit breaker, measuring sensors, protection relay, communication system, wiring) can be specified in a single unit.

Initial installations
ABB has already installed eVD4 circuit breakers in switchgear in its own Italian laboratory, where short-circuit tests are performed. Further installations are currently under way using switchgear produced by other manufacturers.

eVD4 circuit-breakers are ideally suited to a wide variety of applications including: protecting cables, overhead lines, transformers, motors, for integration into smart grids, renewable energy schemes and for many other substation applications.

ABB’s Medium Voltage Products business unit provides utility, industrial and commercial customers with safe, reliable and smart technologies for the distribution of electricity. The extensive global offering includes distribution automation products, switching, limiting, measuring and sensing devices, switchgear, modular package and related services.